Under emotional pressure in past? (5)
I believe the answer is:
tense
This clue is a double definition.
'under emotional pressure' is the first definition.
'past?' is the second definition.
(past tense)
'in' is the link.
(Other definitions for tense that I've seen before include "Stressful" , "Attribute of verbs signalling time" , "past, say" , "present, perhaps?" , "Under emotional strain" .)